The present invention relates to an arrangement in an electro-optic circuit that comprises optic sender and receiver components for transforming an electric output signal to an outgoing optic signal and for transforming a received optic signal to an electric input signal, respectively, connection means for an opto conductor on which the outgoing and received optic signals are transmitted, a sender for the electric output signal, and a receiver for the electric input signal.
Electro-optic circuits of this kind are used e.g. located on a printed circuit card in a telecommunication switch. Each circuit card carries a plurality of such electro-optic circuits and in the switch one or more cabinets can contain a plurality of shielded card magazines, each of which contains a plurality of such circuit cards. For increasing the insensitivity towards EMC, i.e. electromagnetical disturbance radiation, senders and receivers are conventionally located far in on the card as seen from its edge located at an outer cabinet wall, below denominated card front. On the card front there are seated a number of connection devices for connecting an outer opto conductor to two opto conductors leading to the sender and receiver, respectively, of a corresponding sender/receiver pair. For minimizing the risk for interference between sender and receiver of each sender/receiver pair the sender and the receiver are furthermore located remote from each other on the card.
This distribution of the components of the electro-optic circuit counteracts a striving for a more compact architecture of switches of the just described type, while saving or further improving the insensitiveness for EMC, as well as ESD, i.e. electrostatical discharges.